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Home >> Suzuki >> 2007 >> Swift + >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle - AISIN 81-40LE - DTC P0977 To DTC U2105 >> DTC P1781 >> Cause of Failure
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Cause of Failure

DTC P1781

Step Action Values Yes No
1 Did you perform the Diagnostic System Check - Automatic Transmission? - Go to Step 2  Go to Diagnostic System Check - Automatic Transmission
2
  1. Turn OFF the ignition.
  2. Install the scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. Select Store Freeze Frame/Failure Records from the DTC Information menu.
  5. Store Freeze Frame/Failure Records.
  6. Select Clear DTC Information from the DTC Information menu.
  7. Clear the DTC information.
  8. Perform one vehicle drive cycle.
Is the malfunction indicator lamp (MIL) ON?		 - Go to Step 3  Go to Step 7 
3
  1. Select Request DTC by Status from the DTC Information menu.
  2. Request DTC by Status.
Is DTC P1781 displayed?		 - Go to Step 4  Go to Step 7 
4
  1. Turn OFF the ignition.
  2. Disconnect the transmission control module (TCM) wiring connector and the engine control module (ECM) wiring connector.
  3. Measure the resistance between terminal A17 of the TCM wiring connector and terminal K14 of the ECM wiring connector.
  4. Measure the resistance between terminal A7 of the TCM wiring connector and terminal K15 of the ECM wiring connector.
Is the resistance within the specified value?		 0 Ω Go to Step 5  Go to Step 6 
5
  1. Turn ON the ignition, with the engine OFF.
  2. Measure the voltage of terminal A17.
  3. Measure the voltage of terminal A7.
Is the voltage within the specified range?		 11-14 V Go to Step 6  Go to Step 8 
6 Repair the malfunctioning terminals, as necessary.
Did you complete the repair?		 - System OK -
7 Repair the temporary connection failure of the connector. Refer to Wiring Harness and Connector Inspection Diagnosis .
Did you complete the repair?		 - System OK -
8 Inspect the engine for proper operation.
Was a condition found?		 - Go to Diagnostic System Check - Vehicle Go to Step 9 
9
  1. Replace the TCM. Refer to Transmission Control Module Replacement .
  2. Turn OFF the ignition.
  3. Turn ON the ignition, with the engine OFF.
  4. Inspect if DTC P1781 is set.
Is the DTC set?		 - Go to Step 10  Go to Step 11 
10 Replace the ECM. Refer to Engine Control Module Replacement .
Did you complete the replacement?		 - Go to Step 11  -
11
  1. After the repair, use a scan tool Clear Info function and road test the vehicle.
  2. Review the DTC info.
Has the last test failed or is the current DTC displayed?		 - Go to Step 2  System OK
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